2011 R1200 GSA, speedometer hates me!

[Inusleroux]

I'm going to have another go at it tomorrow, I'm just trying to make 100% sure that its not the electrics, another interesting thing is i recieved an email tonight front the previous owner that had it since new(I'm 2nd owner) the only thing he replaced on it was 2 rear speed sensors... in 7 years and 30000 miles... sounds abit odd, any thoughts? And apparently he has no idea you made the repairs in the wire's before. Must have been a ghost.

 

[AustinW]

I have an ABS 2011 GSA, owned from 10,000 to current 87,000 miles. I had the FD rebuilt by Mikeyboy at about 60,000 miles. Before then I had needed to replace the rear speedo sensor twice although it failed more times but removal a clean and a fiddle with it would temporarily fix it. Since the FD rebuild it has been 100% reliable. Coincidence? Possibly. Expensive fix though if that’s the only reason to look at the FD.

 

[Inusleroux]

I have an ABS 2011 GSA, owned from 10,000 to current 87,000 miles. I had the FD rebuilt by Mikeyboy at about 60,000 miles. Before then I had needed to replace the rear speedo sensor twice although it failed more times but removal a clean and a fiddle with it would temporarily fix it. Since the FD rebuild it has been 100% reliable. Coincidence? Possibly. Expensive fix though if that’s the only reason to look at the FD.

I spoke to Mikeyboy on the phone yesterday, something he brought to my attention is the shim/spacer on the sensor.... i don't have one, maybe previous owner dropped it and never noticed, I'll play with that today.

I BMW mechanic that i know says he has seen them with and without spacers, on the parts list for my model it list a spacer. So worth a try i think.
BTW thanks Mickeyboy for phoning me back on a Saturday

 

[Inusleroux]

I have an ABS 2011 GSA, owned from 10,000 to current 87,000 miles. I had the FD rebuilt by Mikeyboy at about 60,000 miles. Before then I had needed to replace the rear speedo sensor twice although it failed more times but removal a clean and a fiddle with it would temporarily fix it. Since the FD rebuild it has been 100% reliable. Coincidence? Possibly. Expensive fix though if that’s the only reason to look at the FD.

when you say give your sensor a clean, what to you mean? As after some extensive multi meter testing today with a friend that's into electronics we still didn't get anywhere.

Main thing is that we still can't a 100% rule out a electrical fault, as we cant really get proper readings from the sensor... 2 readings +- 700ohm and that never fluctuate but we got about 8.2volt reading from it and this we could fluctuate a small amout by wiggling a magnet infront the sensor. And at the same time the speedo would bounce and go up to 15mph. This tell me no electric fault, but I'm not convinced. Any thoughts people?

 

[AustinW]

when you say give your sensor a clean, what to you mean? As after some extensive multi meter testing today with a friend that's into electronics we still didn't get anywhere.

Main thing is that we still can't a 100% rule out a electrical fault, as we cant really get proper readings from the sensor... 2 readings +- 700ohm and that never fluctuate but we got about 8.2volt reading from it and this we could fluctuate a small amout by wiggling a magnet infront the sensor. And at the same time the speedo would bounce and go up to 15mph. This tell me no electric fault, but I'm not convinced. Any thoughts people?

Clean.... nothing fancy, one or more of: removed it, wiped it down, check/replace the O ring, and carefully reseat it. Disconnect the connector under the seat and clean, quick check and wiggle of the wire from sensor to connector. Most times after that it would start working again, a few times it wouldn’t but would randomly fix itself later. I think once I lifted the tank to check the pins on the ECU - all good of course (a careful look at wiring diagram will tell which pins on the ECU it is) and not sure what I thought I might find or what I would have been able to do about it but worth a look for something really random having occurred. You sound like you are waaay ahead of where I got to with my level of diagnosis. Have you tried a known to be good sensor?

On the ABS models the ECU will display speed based on the front sensor after a few miles so a rear sensor failing is not such a problem.

 

[Inusleroux]

Solve Thanks for advice

Well it was a strange one, but hopefully a can help the next person....

Wiring loom stripped down, 3weeks later, Auto Electrician, plenty conflicting advice from experts, 4 speed sensors later...Yes 4 im obviously an unlucky sod, but it's working now!

I can tell you the ohm's, voltages etc, etc, etc... spacer (centering ring) in or out new Final drive oil, speedo strip down, but it came down to bad advise and NOT FROM The FORUM .

It was serious unluck as it was a simple wire repair but this was not the main fault, it was simply a speed sensor.

 

[DrFarkoff]

Sorry but that's as clear as mud to be honest!

So the fault was ??

Wrong year of speed sensor?

Bad repair to wiring??

4 bad speed sensors?

Glad to hear you got it fixed in the end

 

[Inusleroux]

Sorry but that's as clear as mud to be honest!

So the fault was ??

Wrong year of speed sensor?

Bad repair to wiring??

4 bad speed sensors?

Glad to hear you got it fixed in the end

A bad wire and a speed sensor.

Note to all: i was told speed sensor is a AC generator and produces voltage, this is part correct and I was told there can't be power/voltage in the 2 wires going to the sensor. Completely incorrect.

The 2 wires on my 2011 GSA has 8.6 volt in it, this partially supplies the sensor with power.